摘要
石化厂急冷塔中的哈氏C-276合金和16MnR钢易形成电偶对,在塔中HCl气氛下发生腐蚀。测定了哈氏C-276合金与16MnR钢在10%盐酸中的自腐蚀速率、电偶腐蚀速率和稳态极化曲线,探讨了偶接时间、阴阳极面积比、环境温度及腐蚀液流速对阳极电流密度的影响。结果表明:2种金属偶接后,阴极哈氏C-276合金腐蚀速率得到抑制,阳极16MnR钢腐蚀速率急剧增大;2种金属自腐蚀电位相差超过200 mV,电偶电位接近16MnR钢的自腐蚀电位;随偶接时间延长,电偶电流不断衰减,24 h后趋于稳定;阳极电流密度随阴阳极面积比增大、温度升高而增大,但呈非线性增长,一定程度后增长趋势变缓;流动的腐蚀液中的阳极电流密度大于静止腐蚀液中的。
The galvanic corrosion behavior of Hastelloy C-276 alloy and 16MnR steel in 10%HCl solution was studied.The corrosion rates and steady state polarization curves of two metal materials were measured,and the effects of conjunction time,area ratio of cathode to anode,temperature and flow rate of corrosive fluid on anodic current density were investigated.It was found that the corrosion of Hastelloy C-276 alloy was retarded when it was coupled with 16MnR steel,but the corrosion rate of 16MnR steel anode rose significantly.The gap between the corrosion potentials of the two types of metal materials was over 200 mV,and the galvanic potential was close to the corrosion potential of 16MnR steel.The current of the galvanic couple continuously decreased with extending coupling time and tended to stabilize after 24 h of coupling.Besides,the anodic current density rose with increasing area ratio of cathode to anode and temperature as well,but did not vary linearly and tended to vary slowly at some point.Moreover,the anodic current density in flowing organic corrosive fluid was higher than that in stationary corrosive fluid.
出处
《材料保护》
CAS
CSCD
北大核心
2011年第1期49-51,8,共3页
Materials Protection
